You have three testicles?
Mmmhmm

"Hey, check out my collection of bottle caps"
disinterested response: "mmhmm"
OR

"Hey check out my wifes new tits!!"

response: "MMMMMMMMMHMMMMMMMM"

I am going to get me some tonight!

mmhmm!

Johonny: do you want some pig ears?

Me: mmhmm

"mmmmhmmmm" -(base version)
Use when you know someone is just full of it,ie "whatever","ninja please"

"mhm" - (the interruptor)
Use for quickly interrupting someone, case in point, If you just want that person to shut up

"mmmmmmmhmmmmmmmm" - (extended version)
Use when you know that person is full of bullsh*t.

"mmhmmmmmmm" (extended ending)
Use when you know that person is being mischievous.

"MMMHMMMM" - (physical)
Use with body language to call someone out, ex. turn your head, snap your finger, roll your eyes

"M&MHM&M" - (disguise)
The use of M&M's candy, not necessarily for consumption, but for costume purposes i.e. Halloween.

"mmm-H&M-mmm" - (clothing)
The relentless pursuit of clothing oneself with offerings from various fashion retailers such as H&M, Urban Outfitters, American Apparel, Forever21 (Exluded: Abercrombie)

American: You had sex together?
Mexican: Mmhmm

Chinese: Ni hao ma?
American: Mmhmm

ben: i won a million dollars!
andrea: mmhmm shaniqua